Lime kiln with pyrometer mechanism



March 26, 19 A. E. TRUESDELL LIME KILN WITH PYROMETER MECHANISM FiledJan. 15, 1926 2 Sheets-Sheet At Iva.

e d a mu r. n e E r 1U h II r A A. E. TRUESDELL LIME KILN WITH PYROMETERMECHANISM March 26, 1929.

2 Sheets-Sheet 2 Filed Jan. 15, 1926 v Fig. 6.

Invenror. ArThur E. Truesdell bYHV-M M A1 Tys.

Patented Mar. 26, 1929.

uni-tree s'm'rssi antenna is. 'rnonsnnm, or PITTSFIELD, MASSACHUSETTS.

I LIME KILN WITH PYROMETEB MECHANISM.

Application filed January 15, 1.9%. Serial No. 81,418.

This invention relates to lime kilns and the like and particularly tothose kilns which employ a pyrometer mechanism for determining thetemperature in the stack. To

get a proper reading of the pyrometer it is necessary to insert the endthereof into the interior of the stack for a distance of six inches ormore but if the pyrometer remains in this position when the lime orother mam terial is being withdrawn from the bottom of the stack thereis every likelihood that the pyrometer will be broken by the downwardmovement of the material in the stack.

it is one of the objects of my present invention to provide novel meansto indicate I that the pyrometer is in operative position whenever anattempt is made to withdraw lime from the bottom of the stack at a timewhen the pyrometer is thus positioned.

A lime kiln is usually provided at its lower end with a hopper in whichthe burnt lime accumulates and the hopper is provided with a closure,usually in the form of so-called shears, which may be opened wheneverthe burnt lime is to be withdrawn.

In the preferred embodiment of my invention l have provided meansassociated with the shears which will operate to give an indicationwhenever an attempt is made 3Q to open the shears while the pyrometer isin its operative position. The indications may be either in the natureof, a signal, either audible or visual, which will be given whenever anattempt is made to open the shears while the pyrometer is in itsoperative position or may be in the nature of a lock device which willlock the shears from opening when the pyrometer is in such position.Where the lock form of indication is employed T will preferably soconstruct the lock that so long as the pyrometer is in its operativeposition within the kiln the shears will be locked and will be releasedonly when the pyrometer is withdrawn from the kiln chamber.

Furthermore the indicating m e a n s, whether in the form. of a signalor a lock for the shears, is preferably so constructed that it may beused for locking the pyrometer in its withdrawn position, the indicatingdevice at this time being held inoperative so that the material may befreely withdrawn from the stack without giving any signal indication.When, however, the pyrometer is introduced into the stack forthe'purpose Kit) of obtaining a pyrometer reading then the signal willbe operative to give indication in case an attempt is made to withdrawmaterial from the stack. I

In order to give an understanding of my invention l have illustrated inthe drawings, some selected embodiments thereof which will now bedescribed after which the novel fpatures will be pointed out in theappended c aims.

Fig. 1 1s a view in elevation of a vertical kiln embodying my invention;

Fig. 2 is a section on the line 2-2, Fig. 1 showing the shears forclosing the hopper;

Fig. 3 is an enlarged section on the line 83, Fig. 2;

Fig. 4c is a fragmentary view in elevation showing a differentembodiment of the invention;

Fig. 5 is a fragmentary sectional view showing the details of thethree-way. valve used in Fig. 4:;

Fig. 6 is a-view 1n elevation showing a differentfimbodiment of theinvention; Fig. 7 is a fragmentary view in elevation showing the deviceillustrated in Fig. l but with the pyrometer in its operative positionfor taking the reading;

Fig; 8 is a fragmentary sectional view of the switch used in the deviceshown in Fig. 6;

Fig. 9 is a diagrammatic View illustrating a different embodiment of theinvention.

Referring first to Fig. 1, l designates the stack of a kiln which isprovided with the usual chamber2 in which the limestone to be burned isplaced. 3 indicates the usual furnace employed in connection with theburning of the lime and 4 is the hopper at the bottom of the stack inwhich the burnt lime accumulates.

The hopper is open at the bottom and is provided with a closure forclosing the opening, which closure may be removed to permit the burntlime to be discharged from the hopper. The closure herein shown is inthe form of the familiar fiat shears which is commonly-used in limekilns of this nature. These flat shears comprise the two plate members 5which are pivoted at 6. Each member is provided with a handle 7 by whichit may be'manipulated. When the handles are separated from each otherthe closure plates 5 will be similarly separated thus provlding anopening in the bottom of the hopper through which the burnt lime may bedischarged. By closing the plates together the opening is closed.

These parts are or may be all as usual in kilns of this type and form-nopart of my present invention.

8 indicates a pyrometer of any appropriate type by means of which thetemperature of the lime in the chamber 2 may be ascertained while thekiln is in operation. This pyrometer extends through an opening 9 in thewall of the kiln and when it is functioning to give a temperatureindication the inner end 10 thereof will be projected into the chamber 2for an appropriate distance.

For practical operation the best position in which to utilize thepyrometer is at about the point shown, that is, at a point above thefurnace, but this point is entirely out of reach of a person standing onthe firing floor 60 from which the furnace is fired. I have, therefore,provided means for operating the pyrometer which is accessible from thefiring floor 60. This means consists of a lever 11 pivoted at 12 to thestack and connected to the outer end of the pyrometer i so that on theswinging of the lever toward the kiln from the full to the dotted lineposition, Fig. 6, or into the position shown in Fig.7 the pyrometer willbe placed in its operative position with the end 10 situated within thekiln chamber and in appropriate position to secure the pyrometerreading.

The lower end of the lever 12 is .provided with a handle 13 by which itmay be manipulated and this handle is situated within convenient reachof a person on the firing floor 60. With the above described means thepyrometer may be projected into the kiln as shown in Fig. 7 or withdrawnfrom the kiln as shown in Figs. 1 and 6, while the kiln is in operation.

In addition to this feature relating to the means for operating thepyrometer my invention also includes means which is operative to give anindication whenever an at tempt is made to open the shears at a timewhen the pyrometer is in its operative position shown in Fig. 7. Asstated above this indication may be in the nature of a signal which willbe given under these circumstances or may be in the nature of a devicetolock the shears from being opened under h time droppmg into a verticalpositlon shown similar circumstances. In the case of the lock the devicewill operate to prevent any lime from being withdrawn from the hopperwhile the pyrometer is in its operative pos1- tion, the shears beingreleased and being free to be 0 ened when the pyrometer is withdrawnfrom the kiln as shown in Fig. 1.

, Figs. 1 to 8 of the drawings show embodiments of the invention inwhich the indicating device is in the form of a means for locking theshears from being opened at. a

time when the pyrometer is in its operative positionand these figuresalso show means for locking the pyrometer in its withdrawn position whenthe shears are unlocked so that there is an interlocking connectionbetween the pyrometer and shears which will prevent the pyrometer frombeing inserted when the shears are unlocked and conversely will preventthe shears from being opened when the pyrometer is in its operativeposition.

One interlocking mechanism operating in this Way is shown in Fig. 1. Thelock for the shears comprises a locking member 14 having two projections15 adapted to embrace the two handles 7 of the shears as shown in dottedlines Fig. 3, and when so embracing the handles preventing them frombeing separated. In Fig. 1 this l0ck ing member is carried by a lever 16pivoted at 17 and the end of the lever is connected by a link 18 to alocking arm 19 pivoted to the kiln at 20.

21 indicates a collar or shoulder onthe pyrometer-actuating lever 11 andwhich co operates with the locking arm 19 to hold the lock 14 ininoperative position.

The weight of the link 18 and locking arm 19 is such that when thelocking arm is released the weight thereof together with that of thelink 18 will overbalance the lock 14 and will raise the latter into itsoperative position shown in dotted lines Fig. 3; The shears lock 14 isheld inoperative when the pyrometer is withdrawn by the engagement ofthe end of the locking arm 19 with the collar 21 as shown in Fig. 1.When the parts are in this position the end of the arm 19 resting on thecollar 21 will hold he shears lock 14 released and the engagement of thelever 11 with the end of the arm 19 will hold the pyrometer withdrawn.The material may, therefore, be freely withdrawn from the hopper withoutdanger of injuring the pyrometer as the latter is locked in itswithdrawn position.

When it is desired to take a pyrometer reading the operator will firstpull the lever 11 backwardly sufficiently to release the arm 19 from thecollar 21 and when this occurs the weight of the arm 19 and the link 18will overbalance that of the lock 14 so that the latter will be raisedinto the position shown in Fig. 7 and in dotted lines Fig. 3, thuslocking the shears, the arm 19 at this time locked, no material can bewithdrawn from the kiln and, therefore, the pyrometer is relieved ofanydanger of being broken by downward movement of the material into thehopper.

After the pyrometer reading has been taken the pyrometer may bewithdrawn by swinging the lever the shears may be unlocked by raisingthe locking arm 19 and again engaging the arm with the collar 21 on thelower end of-the lever 11 thus locking the pyrometer in its withdrawnposition and also maintaining the shears lock inoperative.

It will thus be' seen that with the device shown in Fig. 1 the pyrometercannot be introduced into the kiln except when the hopper shears arelocked and the pyrometer will be locked in its withdrawn position solong as the shears remain unlocked. The locking of the shears serves asan indication that the pyrometer is in its operative position.

In Fig. l ll have illustrated a little different embodiment of theinvention. In this device the lock for the shears'is pneumatically orhydraulically operated. The lock, which is indicated at 14, is carriedby an arm 22 pivoted at 23, said arm having rigid therewith anupstanding arm 24 to the upper end of which is connected a pistonoperating in a cylinder 25. 26 is a pipe leading to the cylinder andthrough which motive fluid under pressure is introduced into thecylinder 25. This pipe has a three-Way valve 27 therein which iscontrolled by an arm 28 similar to the locking arm 19 in Fig. 1.

The three-way valve 27 has a supply pipe 51 leading thereto and anexhaust port 52. The valve is of the plug valve type having a port 53which upon turning of the plug establishes a communication, between thesupply pipe 51 and the pipe 26 leading to the cylinder or between thepipe 26 and the exhaust port 52. Normally when the shears are unlockedas shownin Fig. 4, the cylinder will be exhausted, this being thecondition when the valve is in the position shown in Fig. 5, thusestablishinga communication between the pipe 26 and the exhaust 52. Whenthe valve is in this position the arm 28 thereof rests'on the collar 21,said collar locking the arm in this position and the arm locking thelever 11 Withdrawn.

When it is desired to use the pyrometer the arm 11 is pulled backwardlya suli'icient distance to release the arm 28 trom -the col lar 21 andthe arm 28 may then be swung downwardly thus turning the'valve so thatthe port 53 will connect the supply pipe 51 and the pipe 26. This willallow motive fluid to flow into the cylinder 25 and wili move the pistonto the right thereby raising the shears lock 14; and lockin the shears.

After the pyrometer; rea ing has been taken the pyrometer is Withdrawnby swinging the lever 11 backwardly and then the valve arm 28 isrestored to the position shown in Fig. 4c, in which position it is heldby the" collar 21 and in which position it locks the lever 11 fromswinging inwardly.

11 outwardly after which This moves the valve into the position shown inFig. 5 and thus exhausts the cylinder and allows the shears lock to dropinto its inoperative position by the weight thereof. 7

In Fig. 6 I have shown a diflerent "embodiment of the invention inwhichthe interlocking is in the nature of an electrical device. In thisembodiment the lock 14'for the shears is carried by an arm 29 pivoted at30 and having integral therewith an upstanding portion 31, the upper end32 of which is in the form of the armature fora magnet 33. The circuit34 of the magnet, which includes a suitable source of electrical supply35 has therein two contacts 36 and 39 which are enclosed in a casing 58preferably ofinsulating material. The contact 39 is aresilient contactand its resiliency will normally hold it in engagement with the contact36 thus closing the circuit 34:. When the switch is opened by separationof the contacts the magnet 33 is de-energized and the shears lock 14will drop by gravity into its inoperative position. When the c rcuit sclosed, however, and the magnet 33 1s energized the armature 32 will beattracted to the magnet thus raising the shears lock 14: into itsoperative position and locking the shears closed. Means are providedwhereby the contacts 39 and 36 will be held separated'thus opening thecircuit so long as the pyrometer 1s withdrawn but will be brought intocontact thus closing the circuit when the pyrometer is inserted into thekiln.

The lever 11 haspivotally connected to its lower end a member 38, theend of which is adapted to enter an opening 59 in the casing 58 and toengage the projecting end of the resilient contact 39. When the partsare in this position, as shown in Figs. 6 and 8, the weight of the lever11 is sufiicient to hold the contacts separated and the circuit open.

Vfhen it is desired to take a pyrometer reading the lever 11 is pulledbackwardly suficiently to withdraw the casing 58 thus allowing thecontacts to close by the resiliency of the contact 39. The

closing of the contacts will energize the magnet 33 and thus causethe'shears lock 14 to be moved into its operative position. WV hen thearm 38 has beenthus withdrawn arm 38 from. the

from the switch casing 58 it Will drop into the dotted line positionFig. 6 and the lever 11 may then be swung inwardly into its dotted lineposition thus projecting the pyrometer into the kiln chamber. When thepyrometer reading has been taken the lever 11 is pulled backwardly towithdraw the pyrometer from the kiln chamber and the lever is held insuch position by re-inserting the end of the arm 38in-to the switchcasing '58 as shown in Fig. 8 thereby opening the circuit and releasingthe shears lock. With .this embodiment also the shears will be lockedbefore the pyrometer is movedinto the shown in Fig. 4, the locking ofthe shears pyrometer constitutes an indication that the is 1n itsoperative position.

Instead of an indication in which'the shears are locked when thepyrometer is in its operative position I may employ an indication in theform of a signal which will give this information. Such a signal may beeither an audible signal or a visual signal and may be construcetd sothat if an attempt is made to open the shears at a time when thepyrometer is in its operative position as shown in Fig. 7 the audible orvisual signal will be given to apprise the operator that the pyrometeris in its operative position and hence would be liable to be injured ifmaterial is withdrawn from the kiln.

In Fig. 9 I have illustrated an embodiment of the invention having thissignal indication. In this construction the end 6 of each shear memberis provided with a contact 62, said'contacts so arranged that they Willbe closed whenever the shears are opened. These contacts 62 are in acircuit 63 having a signal 64 therein and also having two contacts 36and 39 similar to the contacts shown in Fig. 8 and which areheld open byan arm 38 on the pyrometer-operating lever 11 when the pyrometer isretained in its withdrawn position. So long as the pyrometer is in itswithdrawn position and the circuit 63 is open at the contacts 36, 38then, of course, the closing of the contacts 62 by the opening of theshears will have no effect in operating the signal 64. ltf, however,.the pyrometer is placed in its operative position as shown in Fig. '7and in dotted lines Fig. 6 in which case the arm 38 has been withdrawnfrom the switch casing 58 and the circuit is closed at the contacts, 36,39, then if an attempt is made to open the shears to withdraw the limefrom the hopper the contacts 62 will be closed thus closing the signalcircuit and operating the signal 64. The operation of the signal 64:,whether it be a visual signal or an audible signal will give informationto the operator that the pyrometer is in its operative position and willthus prevent him from proceeding to withdraw lime from the hopper inignorance of the fact that the pyrometer is projecting into the kilnchamber.

I claim.

1. The combination with a stack kiln having a chamber in which materialis burned, said kiln being provided with an opening through which theburnt material is discharged and a closure for said opening, of

a pyrometer, actuating means for projecting the pyrometer into thechamber of the stack or withdrawing it therefrom while the kiln is inoperation, and means controlled by the pyrometer-actuating means toindicate whether the pyrometer is projected into the stack or not.

2. The combination with a stack kiln having a chamber in which materialis burned, said-kiln being provided with an opening through which theburnt material is discharged and a closure for said opening, of apyrometer, means for projecting the pyrometer into the chamber of thestack or withdrawing it therefrom while the kiln is in operation, andmeans controlled by the pyrometer-moving means to give an indicationwhen an attempt is made to open the closure at a time when the pyrometeris in its operative position. f I

3. The combination with a stack kiln having a chamber in which materialis burned and also having a hopper in which the burnt materialaccumulates, of a pyrometer adapted to be projected into the chamber ofthe stack or withdrawn therefrom while the kiln is in operation, aclosure for the hopper, and means rendered operative when the pyrometeris projected into the kiln chamber to prevent the closure from beingopened.

4. The combination with a stack kiln hav ing a chamber in which materialis burned and also having a hopper in which the burnt materialaccumulates, of a closure for the hopper, a pyrometer adapted to be projected into the chamber of the stack or withdrawn therefrom while thekiln is in operation, a lock for locking theclosure in closed position,and means to render the lock operative when the pyrometer is projectedinto the stack chamber.

5. The combination with a stack kiln having a stack chamber in whichmaterial is burned and also having a hopper in which the burnt materialaccumulates, of a pyrometer adapted to be projected into the stackchamber or withdrawn therefrom, a closure for the hopper, a lock for theclosure, and means to lock the yrometer in its withdrawn relation whenthe closure is unlocked.

6. The combination with a stack kiln hav ing a stack chamber in whichmaterial is burned and also having a hopper in which burnt materialaccumulates, of a closure for the hopper, a pyrometer adapted to beprojected into the stack chamber or withdrawn therefrom, means forholding the pyrometer in its withdrawn relation, and means to indicatewhen an attempt is made to open the closure at a time when the pyrometeris released from its withdrawn position.

7 In a kiln, the combination with a stack having a chamber, of a firingfloor, a pyrometer adapted to be projected into the kiln chamber at apoint considerably above having a chamber,

rometer adapted to be projected into said chamber at a pointconsiderably above the firing floor, a lever pivoted to the stack andconnected to the pyrometer and extending to within reach of an operatoron the firing floor, wherebythe pyrometer may be withdrawn from orprojected into the kiln chamher by swinging movement of the lever, and

means to retain the lever in the position 1t occupies when the pyrometeris in withdrawn position.

9,;In a stack kiln, the combination with a stack chamber in whichmaterial is burned, of a hopper in which the burnt material accumulates,a closure for the hopper which may be opened to permit discharge ofmaterial therefrom, a pyromet'er adapted to be projected into the stackchamber or withdrawn therefrom, a lock for locking the closure in closedrelation, and means to render the lock operative when the pyrometer isprojected into the chamber.

10. In a stack kiln, the combination with a stack chamberin whichmaterial is burned, of a hopper in which the burnt material acclosure--opening, a closure.

cumulates, said hopper having an opening through which material isdischarged, a for said opening, a pyrometer adapted to be projected "ntooperative position in the stack chamber to indicate the temperaturetherein or to be withdrawn from thechamber, actuating means for placingthe pyrometer in elther of these positions, means for holding thepyrometer in its withdrawn position, a lock for the 010- sure, and meansfor rendering the lock operative when the pyrometer is in its operativeposition and inoperative whenthe pyrometer is held in its withdrawnposition.

11. In a stack kiln, a stack chamber in which material is burned, of ahopper in which the burnt material accumulates said hopper having adischarge for said opening, a pyrometer adapted to be projected intooperative position in the stack chamber for indicating the temperaturetherein or to be withdrawn from said chamber, means to 0perate thepyrometer and place it'in either position; an indicator, and means torender the latter operative to give an indication when an attempt ismade to open the clo sure at a time when the pyrometer is in itsoperative position.

In testimony whereof, I have signed my name to this specification.

ARTHUR E. TRUESDELL.

the combination with

